The goal of this application is to produce a cadre of scientists with expertise in the epidemiology of infectious diseases. These scientists will be characterized by their knowledge in this area and their appreciation of the diversity of issues that must be dealt with in conjunction with the study of infectious diseases. In light of the particular research strengths of the participating faculty, the primary, although not exclusive, focus of research experience within the training program will be HIV disease and its related complications. Graduates of the program will serve as future leaders in the effort to rapidly identify, prevent and manage emerging and reemergent infections in a dramatically changing global environment. To achieve this goal, scientists will need to gain a full understanding of the dynamics of disease transmission, patterns of disease presentation among differing populations, as well as the socioeconomic factors contributing to these patterns. The investigators listed in this application encompass a large multidisciplinary, international group, combining expertise in HIV clinical trials, basic science, bacterial and viral infections and preventive medicine. They include investigators from the School of Public Health, Division of Epidemiology, Departments of Medicine, Pediatrics, Informatics, and Pathology, at the Columbia College of Physicians & Surgeons. Training will include coursework in epidemiology and informatics with an emphasis on the epidemiology of infectious diseases, as well as the opportunity for fieldwork at the New York City Department of Health and research experience with the faculty serving as mentors in this program. Research opportunities include projects that are laboratory or clinically based as well as projects that are local/domestic (Harlem, Washington Heights) or international (South Africa, Uganda) in scope. Candidates will be recruited from the Infectious Diseases Fellowship Training Program in the Department of Medicine or Pediatrics, one of the two doctoral programs in the School of Public Health, or from the School of Nursing postgraduate training program. All trainees will be expected to pursue a Master?s of Public Health or Science or doctoral degree as part of this program.